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Weakness (CWE)

CWE-1289: Improper Validation of Unsafe Equivalence in Input

Base Incomplete

The product receives an input value that is used as a resource identifier or other type of reference, but it does not validate or incorrectly validates that the input is equivalent to a potentially-unsafe value.

How to prevent it (1 mitigation)

  1. Implementation

    Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.

    When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue."

    Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.

Source: MITRE CWE-1289

All Critical High Medium Low Exploited only Public exploit

3 results · Clear filters · Feed

  • Critical 9.2
    CVE-2026-106445 Public exploit

    Handlebars: JavaScript Injection via Own Property Check Bypass

    Handlebars provides the power necessary to let users build semantic templates. From 3.0.0 until 4.7.10, Handlebars lookupProperty returns Function.prototype.constructor before applying the prototype-access deny list because constructor is an own property of F…

    handlebars-lang handlebars.js handlebars node-handlebars Debian Ubuntu npm
  • Medium 6.5
    CVE-2026-47729 Public exploit

    Squid: Memory disclosure in FTP gateway

    Squid is a caching proxy for the Web. Prior to 7.6, due to an improper validation of syntactic correctness of input in the FTP gateway (src/clients/FtpGateway.cc), Squid is vulnerable to an out-of-bounds read: when a listing entry date in the TypeA or TypeB d…

    squid-cache squid squid squid3 Debian Ubuntu Alpine
  • Medium 6.5
    CVE-2026-48710 Exploited Public exploit EPSS 70%

    Starlette has missing Host header validation that poisons request.url.path, bypassing path-based security checks

    Starlette is a lightweight ASGI framework/toolkit. Prior to version 1.0.1, the HTTP `Host` request header was not validated before being used to reconstruct `request.url`. Because the routing algorithm relies on the raw HTTP path while `request.url` is rebuil…

    Kludex starlette starlette starlette Debian Ubuntu Alpine PyPI
    KEV Sep 2, 2026